<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>SVG</title>
  <style>
    circle {
      animation: tobig 2s infinite;
      animation-timing-function:ease-in;
    }

    @keyframes tobig {
      0% {r:10; opacity: 0;}
      100% {r:40; opacity: 1;}
    }
  </style>
</head>

<body>
  <svg width="100%" height="100%" version="1.1" xmlns="http://www.w3.org/2000/svg">


    <circle cx="42" cy="42" r="40" stroke="black" stroke-width="2" fill="red" />

    <rect x="0" y="42" width="84" height="42" fill="#fff" />
  </svg>
</body>

</html>